Fishing tool



Feb. 10, 1942.

A. D. LARSON I FISHING TOOL Filed March 7, 1941 241.5507 0. MASONINVENTOR ATTORNEY Patented Feb. 16, 1942 4 Claims.

This invention relates to fishing tools and more particularly to suckerrod sockets.

Sucker rod joints ordinarily include a box carried by one section of rodfor receiving a pin carried by another section of rod. As the entiresucker rod string is reciprocated during the pumping of a well thesucker rod joints suffer severe strain and wear. They oftentimes becomeso worn as to be almost egg-shaped in cross section. When the sucker rodstring has operated continuously over a considerable period of time themetal of which the various sections are made often becomes fatigued,usually at the joint, causing breakage of the string and leaving aconsiderable portion of the string in the well.

Many tools of generally known construction are capable of entering thewell and grasping a normally sized sucker rod box or pin which is notunduly worn. Few of them, however, can accommodate various sizes of bothboxes and pins worn in varying degrees.

It is the chief object of my invention to provide a tool which can belet down into the well and which will receive a sucker rod box or pin,and which then can be operated from above to grip the box or pinregardless of its diameter or degree of wear, and which may then bewithdrawn to remove that portion of the sucker rod string which wasbroken off in the well.

As stated, my invention will accommodate various sizes of sucker rodjoints in various degrees of wear and in varying cross sectional shapeswithout the necessity of removing the tool from the well and changing oradjusting any of its parts.

The details in the construction of a preferred form of the invention,together with other objects attending its production, will be betterunderstood from the following description when read in connection withthe accompanying drawing which is chosen for illustrative purposes only,and in which Figure 1 is a vertical, central, longitudinal View thru atool embodying the invention, with a portion of a sucker rod jointlocked within the body of the tool;

Figure 2 is a similar view of the tool in unlocked or open position;

Figure 3 is a bottom plan view of a portion of the tool illustrated inFigures 1 and 2;

Figures 4, 5 and 7 are horizontal sectional views taken along extensionsof the lines 4, 5 and l, of Figure 2; and

Figure 6 is a horizontal sectional view taken along the extension of theline 6 of Figure 1.

Like characters of reference designate like parts in all the figures.

The embodiment of the tool illustrated includes a tubular body Ill, thebore of which is reduced eccentrically at its lower end, forming aneccentric shoulder ll. Its extreme end is beveled as indicated by thenumeral ['2 to facilitate entry of a broken sucker rod joint into thelower end of the tool. A replaceable eccentric collar I3 is held againstrotation on the eccentric shoulder H by means of a set screw [4 passingthru a slot l5 in the wall of the body Hi. This collar I 3 is beveledslightly outward on its upper surface as indicated by the numeral 46 toform a relatively sharp inner edge for contact with any part of thesucker rod joint. It is also made of extremely hard metal to resistWear. The upper end of the tubular body It is threaded to receive a headI! which is threaded at its upper end for attachment to a fishingstring. The head is hollow at its lower end to receive a spring I8.Intermediate its ends the head H is provided with a plurality ofperforations H) which afford communication with the interior bore in thelower end of the head. These perforations I9 permit paraffin and otherdetritus which may have accumulated on the inner walls of the productiontubing to pass thru the tool without obstructing the downward passage ofthe tool.

Inside the body or barrel l 0 I provide an eccentric sleeve 29 which ispreferably split longitudinally along its thinnest wall. This sleeve 20rests on the upper edge of the collar I3, and it is rotatable andslidable within the barrel It. When this sleeve is rotated to oneposition its bore is concentric with the bores of the collar l3 and withthe bore in the extreme lowerend of the barrel It), as inFigure 2L Whenit is rotated in either direction its bore has the relation to the boresin the collar l3 and in the lower end of the barrel H) as shown inFigure 6. In other words the open space thru which an object may passaxially is considerably reduced in diameter by the rotation of thissleeve.

As a means of locking the sleeve in either of the positions shown inFigures 1 and 2 I provide a plug ii for its upper end. This plug has anupper portion of relatively largediame-ter which is of such size as tobe rotatable and slidable within the barrel It. The lower portion 22 ofthis plug is also cylindrical but is eccentric with respect to the axisof the upper portion. The diameter of this lower portion is such that itwill enter the upper end of the sleeve 20. An eccentric shoulder 23 isthus formed between the upper and lower portions of this plug. Extendingdownwardly from the shoulder are a plurality of pins 24 and 25 which areadapted to be received in complemental holes in the upper edge of thethickest portion of the wall of the sleeve 20. When the plug is seatedin the upper end of this sleeve 29, the pins 24 and 25 thus lock theplug and the sleeve for rotation together, while the shoulder 23 limitsthe penetration of the plug into the sleeve. In the exterior surface ofthe largest portion of this plug 2| a circumferential groove 26 isformed. This groove extends approximately half way around the plug andat each of its ends it communicates with short axially extending grooves21 and 28. These grooves are adapted to receive an inwardly projectingpin 29 made integral with or set rigidly in the wall of the barrel ID,as shown in Figure 4. A spring I8 bears against the upper end of thisplug 2| and thus normally keeps the sleeve ID seated on the upper edgeof the collar l3. Another axially extending groove 30 (Figure 3) isprovided in the lower portion 22 of the plug to permit the entrance ofthe pin 29 into the groove 26. As indicated by the dotted lines in bothFigures 1 and 2, the plug 2| is provided with a central bore 3|, whichfacilitates the passage of paraffin and other detritus thru the tool.The extreme lower surface of the plug 2| is provided with a plurality ofridges 32, or is roughened in any other manner to afford a substantiallynon-skid surface.

The pin 29 is placed at such a distanc from the collar I3 that the pin29 must at least have partially entered either the grOOVe 21 or thegroove 28 before the plug can assume its position of maximum penetrationinto said sleeve, in either of which positions both the plug and thesleeve are locked against rotation with relation to the barrel. Thetension of spring l8 naturally keeps the plug seated in the upper end ofthe sleeve 20.

In operation, with the sleeve in the relative position shown in Figure2, the tool is let down into the well thru the production tubing untilthe broken upper end of the sucker rod string passes into the bore ofthe tool. The upper end of the broken rod or joint contacts theroughened lower surfac of the plug 2| forcing the plug to move upwardslightly within the barrel H] until it contacts the lower end of thehead N. This longitudinal movement of the plug brings the groove 26 intoalignment with the pin 29 on the inside of the barrel. The barrel is nowrotated 180 by rotation of the fishing string to which the tool isattached, the pin 29 traveling through the groove 26 until it reachesthe groove 21 which prevents further rotation. Weight is then removedfrom the tool and the spring I8 again forces the plug 2| downward in thebarrel, the pin 29 entering the axial groove 21. During its rotation theplug has also forced the sleeve 29 to rotate with it, and the interiorbore of the tool has been reduced, as shown in Figure 6. This reductionin diameter forces the sucker rod joint toward the thickest part of thecollar I3, and when a lifting forc is applied to the tool this collar l3contacts some portion of the sucker rod joint and positively preventsits movement out of the lower end of the tool. The tool is then simplywithdrawn from the well and the broken sucker rod string is withdrawnwith it. A reversal of these steps will naturally result in releasingthe work being handled, if desired. This ability to release the work isan important feature of my invention, and to my knowledge there is nosuch tool in general commercial use which can be 0D- erated to releasethe work until after it is withdrawn from the well.

While I have described and illustrated a specific embodiment of myinvention, I am aware that numerous alterations and changes may be madetherein without departing from the inventive principle, and I do notwish to be limited, except by the prior art and by the scope of theappended claims.

.I claim:

1. A fishing tool comprising: a barrel having at its lower end a workreceiving bore of abruptly reduced diameter which bore is eccentric withrelation to the remainder of the larger bore in said barrel; aneccentric sleeve of such exterior diameter as to fit snugly butrotatably within said larger bore, the diameter of the sleeve bore andthe eccentricity thereof being substantially the same respectively asthe diameter and eccentricity of the reduced bore in said barrel; aneccentric plug slidable but non-rotatable in the upper end of saidsleeve, and slidable and rotatable in the large bore of said barrel;co-operating means on plug and barrel for limiting the rotationalmovement of said plug and said sleeve, said means also being adapted tolock said plug, and consequently said sleeve, in at least two positionsof orientation with relation to said barrel; and a tool head for saidbarrel.

2. A fishing tool comprising: a barrel having the major portion of itsbore of relatively large diameter and substantially concentric with itsexterior wall surface, and having at its lower end a communicatingeccentric bore of abruptly reduced diameter; an eccentric sleeve of suchexterior diameter as to fit snugly but rotatably within the larger boreof said barrel, the diameter of the sleeve bore and the eccentricitythereof being substantially the same respectively as the diameter andeccentricity of the reduced bore in said barrel; an eccentric plug theeccentric Y portion of which is slidable but non-rotatable in the upperend of said eccentric sleeve, and the remaining portion of which fitssnugly but is rotatable and slidable within the large bore of saidbarrel adjacent the upper end of said sleeve; a circumferentiallyextending groove cut in the exterior of the last mentioned portion ofsaid plug, the opposite ends of said groove each communicating with ashort axially extending groove of similar depth also cut into theexterior of said plug; an inwardly projecting pin carried on the innersurface of the barrel and adapted to travel in the circumferentialgroove when said barrel is rotated with relation to said plug andsleeve, and to enter either of the axial grooves for locking the barrelagainst rotation with relation to said plug and sleeve; spring meansexerting force on said plug and on said barrel to urge the two unitsinto locked, relatively non-rotatable relation; and a tool head for saidbarrel.

3. A fishing tool comprising: a barrel having a concentric upper boreand an eccentric lower bore; a similarly eccentric sleeve in said upperbore rotatable with relation to said lower bore to vary the crosssectional size of the axial free passage area thru said barrel; a plugnon-rotatably secured in the upper end of said eccentric sleeve, saidplug, however, being rotatable within said barrel; and co-operatingmeans on plug and barrel for locking the two in different positions ofrelative orientation.

4. A fishing tool comprising: a barrel having a concentric bore; aremovable eccentrically bored insert adapted to be rigidly but removablysecured in the lower end of the bore of said barrel; a similarlyeccentric sleeve in the concentric bore of said barrel rotatable withrelation to said insert to vary the cross sectional size of the axialfree passage area through said barrel; a plug non-rotatably secured inthe upper end of said eccentric sleeve, said plug being rotatable withinsaid barrel; and co-operating means on plug and barrel for locking thetwo in different positions of relative orientation.

ALBERT D. LAB/SON.

